
Trailer Anti-Lock Brake System
Warning Light
If your vehicle is connected
to a trailer with anti-lock
brakes, this light should
come on briefly, as a
check, when you turn on
the ignition.
When this light comes on and stays on, it means there
is something wrong in the trailer anti-lock brake
system. Have the system repaired immediately.
If an anti-lock brake system equipped trailer is not
connected, this light is not functional.
Engine Coolant Temperature Gage
This gage shows the engine coolant temperature. If the
gage pointer moves into the red area, your engine
coolant might have overheated and your engine may be
too hot. You should pull off the road, stop your vehicle
and turn off the engine as soon as possible.
SeeEngine Overheating on page 5-36. If you have a
Caterpillar
®diesel engine, also see your Caterpillar®
Operation & Maintenance Manual.
United StatesCanada
3-35

Low Washer Fluid Warning Light
This light will come on
when your vehicle is low
on windshield washer fluid.
For more information, seeWindshield Washer Fluid on
page 5-44.
Check Gages Warning Light
This light will come on as
you’re starting the engine,
just as a check.
If this light comes on and stays on while you are driving.
it means that either your engine coolant temperature
gage or your engine oil pressure gage may be showing
a reading in the warning zone.When the check gages light comes on, you will also
hear a warning tone. The tone and the light will
stay activated until the problem is corrected.
This light may also come on if your vehicle is equipped
with the optional automatic engine shutdown system
and engine shutdown has begun. SeeEngine Alarm and
Automatic ShutdownunderStarting Your Diesel
Engine on page 2-14.
Fuel Gage
Your fuel gage is located
on the right side of your
instrument panel cluster.
When the ignition is on, your fuel gage lets you know
about how much fuel you have left. When the gage first
shows empty, you’ll still have a little fuel left, but you
should get more fuel soon.
3-42

The following explains your cooling system and how to
add coolant when it is low. If you have a problem
with engine overheating, seeEngine Overheating on
page 5-36.
A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
•Give freezing protection down to−34°F (−37°C).
•Give boiling protection up to 252°F (122°C).
•Protect against rust and corrosion.
•Help keep the proper engine temperature.
•Let the warning lights and gages work as they
should.
Notice:Using coolant other than DEX-COOL
®may
cause premature engine, heater core or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your vehicle.
What to Use
Use a mixture of one-halfclean, drinkable waterand
one-half DEX-COOL®coolant which won’t damage
aluminum parts. If you use this coolant mixture,
you don’t need to add anything else.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will. Your
vehicle’s coolant warning system is set for the
proper coolant mixture. With plain water or the
wrong mixture, your engine could get too hot
but you would not get the overheat warning.
Your engine could catch re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.
Notice:If you use an improper coolant mixture,
your engine could overheat and be badly damaged.
The repair cost would not be covered by your
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core and
other parts.
If you have to add coolant more than four times a year,
have your dealer check your cooling system.
Notice:If you use the proper coolant, you do not
have to add extra inhibitors or additives which claim
to improve the system. These can be harmful.
5-33

Engine Overheating
You will find a coolant temperature warning gage on
your vehicle’s instrument panel, as well as a low coolant
warning light. Your vehicle also has a check gages
warning light on the instrument panel.
If Steam Is Coming From Your Engine
{CAUTION:
Steam from an overheated engine can burn
you badly, even if you just open the hood. Stay
away from the engine if you see or hear steam
coming from it. Just turn it off and get
everyone away from the vehicle until it cools
down. Wait until there is no sign of steam or
coolant before you open the hood.
If you keep driving when your engine is
overheated, the liquids in it can catch re. You
or others could be badly burned. Stop your
engine if it overheats, and get out of the
vehicle until the engine is cool.
Notice:If your engine catches re because you
keep driving with no coolant, your vehicle can
be badly damaged. The costly repairs would not be
covered by your warranty.
5-36

Part C: Recommended Fluids and
Lubricants
Fluids and lubricants identified below by name, part
number or specification may be obtained from your
dealer.
Usage Fluid/Lubricant
Engine Oil
(Gasoline
Engine)Engine oil which meets GM
Standard GM6094M and displays
the American Petroleum Institute
Certified for Gasoline Engines
starburst symbol. To determine the
proper viscosity for your vehicle’s
engine, see “Engine Oil” in the
Index.
Engine Oil
(DURAMAX™
Diesel Engine)Engine oil with the letters CI-4 or
CH-4 is best for your vehicle. The
CI-4 or CH-4 designation may
appear either alone or in
combination with other API
designations, such as API CI-4/SL.
These letters show American
Petroleum Institute levels of quality.
To determine the preferred viscosity
for your vehicle’s diesel engine, see
“Engine Oil” in the Index.
Usage Fluid/Lubricant
Engine Oil
(Caterpillar
®
Diesel Engine)See the Caterpillar
®Operation &
Maintenance Manual for engine oil
recommendations.
Engine Coolant
(Caterpillar
®
Diesel Engine)See the Caterpillar
®Operation &
Maintenance Manual for engine
coolant recommendations.
Engine Coolant
(Gasoline
Engine &
DURAMAX™
Diesel)50/50 mixture of clean, drinkable
water and use only
DEX-COOL
®Coolant. See “Engine
Coolant” in the Index.
Hydraulic Brake
SystemDelco Supreme 11 Brake Fluid or
equivalent DOT-3 brake fluid.
Windshield
Washer SolventGM Optikleen
®Washer Solvent.
Clutch Bearing
LubricantClutch Bearing Lubricant (GM Part
No. 12378484 or equivalent NLGI #3
consistency).
Exhaust Brake
Ball Joint Cap
LubricantHigh-Temperature Grease (GM Part
No. U.S. 1051344, in Canada
903037) or NLGI #3 consistency.
Power Steering
SystemDEXRON
®-III Automatic
Transmission Fluid.
6-29

Compact Disc Messages..................................3-56
Control of a Vehicle.......................................... 4-5
Coolant
Engine Temperature Gage............................3-35
Heater, Engine............................................2-23
Low Warning Light.......................................3-36
Surge Tank Pressure Cap.............................5-35
Cooling System..............................................5-38
Cooling System Capacity.................................5-94
Cruise Control................................................3-10
Current and Past Model Order Forms.................. 7-8
Customer Assistance Information
Customer Assistance for Text Telephone
(TTY) Users.............................................. 7-3
Customer Assistance Offices........................... 7-3
Customer Satisfaction Procedure..................... 7-2
Reporting Safety Defects to General Motors...... 7-7
Reporting Safety Defects to the Canadian
Government.............................................. 7-7
Reporting Safety Defects to the United
States Government.................................... 7-6
Roadside Assistance Program......................... 7-4
Service Publications Ordering Information......... 7-7
D
Daytime Running Lamps..................................3-14
Daytime Running Lamps Indicator Light.............3-41
Defensive Driving............................................. 4-2Defogging and Defrosting.................................3-20
Defroster Check..............................................6-27
Diesel Engine
Exhaust Brake............................................2-25
Fuel............................................................ 5-8
Starting......................................................2-14
Starting Your DURAMAX™...........................2-19
Diesel Engine Warm-Up...................................2-16
Differential Lock Control, Inter-Axle....................4-10
Differential Lock Control, Rear Axle...................4-10
Differential Lock Indicator Light.........................3-40
Doing Your Own Service Work........................... 5-4
Dome Lamps.................................................3-15
Door
Locks.......................................................... 2-6
Power Door Locks......................................... 2-7
Door Latches Check........................................6-27
Double-Clutching.............................................2-30
Driver
Position, Safety Belt.....................................1-13
Driving
At Night.....................................................4-17
City...........................................................4-21
Defensive..................................................... 4-2
Drunken....................................................... 4-2
Freeway.....................................................4-22
Hill and Mountain Roads..............................4-23
In Rain and on Wet Roads...........................4-18
Winter........................................................4-25
4

Driving on Snow or Ice....................................4-26
Driving Through Deep Standing Water...............4-20
Driving Through Flowing Water.........................4-20
Dual Tire Operation.........................................5-69
E
Eaton®Fuller®Five and Six-Speed
Transmissions and TTC Spicer Seven-Speed
Transmissions.............................................2-30
Eaton
®Fuller®Nine and Ten-Speed
Non-Synchronized Manual Transmissions........2-32
Electric Air Compressor...................................5-51
Electrical Connections......................................4-36
Electrical System
Add-On Equipment......................................5-86
Fuses and Circuit Breakers...........................5-87
Fusible Links..............................................5-87
Headlamp Wiring.........................................5-86
Power Windows and Other Power Options......5-87
Windshield Wiper Fuses...............................5-87
Elevated Idle/Exhaust Restrictor........................2-21
Engine
Air Cleaner/Filter.........................................5-30
Battery.......................................................5-55
Change Engine Oil Light...............................3-39
Check and Service Engine Soon Light............3-37Engine (cont.)
Checks Before Operating..............................2-22
Coolant..............................................5-32, 5-35
Coolant Heater............................................2-23
Coolant Temperature Gage...........................3-35
Diesel Engine Exhaust Brake........................2-25
Drive Belt Routing......................................5-103
Exhaust.....................................................2-37
Fan Noise..................................................5-43
Oil .....................................................5-20, 5-25
Overheating................................................5-36
Overspeed Warning Light..............................3-39
Reduced Power Light...................................3-41
Shutdown Warning Light...............................3-39
Starting Your Diesel.....................................2-14
Starting Your DURAMAX™ Diesel..................2-19
Starting Your Gasoline..................................2-12
Engine Alarm and Automatic Shutdown..............2-16
Engine Coolant Level Check.............................6-24
Engine Cooling System Service........................6-26
Engine Cover Check.......................................6-28
Engine Oil Additives................................5-23, 5-29
Engine Oil Level Check...................................6-24
Engine Road Speed Governor..........................3-25
Engine Speed Limiting.....................................3-25
Engine Starter Over-Crank Protection.................2-12
Event Data Records (EDR)................................ 7-5
Exhaust Brake Indicator Light...........................3-40
5

G
Gage
Air Pressure...............................................3-44
Check Gages Warning Light..........................3-42
Engine Coolant Temperature.........................3-35
Filter Minder...............................................3-44
Fuel..........................................................3-42
Hourmeter..................................................3-45
Oil Pressure...............................................3-37
Speedometer..............................................3-25
Tachometer.................................................3-26
Transmission Temperature.............................3-40
Voltmeter Gage...........................................3-30
Gasoline
Octane........................................................ 5-6
Specifications............................................... 5-6
Gasoline Engine, Starting.................................2-12
Gasoline Engine Warm-Up...............................2-14
Glass, Mirrors, Lamps and/or Reflectors
Condition Check..........................................6-27
H
Hazard Warning Flashers................................... 3-5
Headlamp High/Low-Beam Changer.................... 3-8
Headlamp Wiring............................................5-86Headlamps On Reminder.................................3-13
Heavy-Duty Trailer Wiring Package....................4-35
Height Adjustment............................................. 1-6
High Idle System (Caterpillar
®Diesel and
Gasoline Engines).......................................2-16
Highway Hypnosis...........................................4-23
Hill and Mountain Roads..................................4-23
Hood
Checking Things Under................................5-18
Latches......................................................5-19
Hood Latches Check.......................................6-28
Horn............................................................... 3-6
Hourmeter Gage.............................................3-45
How to Add Coolant to the Coolant
Surge Tank.................................................5-39
How to Add Fluid............................................5-32
How to Check................................................5-69
How to Check and What to Use...............5-31, 5-32
How to Check Fluid........................................5-61
How to Check Lubricant...................................5-61
How To Check Power Steering Fluid..................5-43
How to Inspect the Engine Air Cleaner/Filter.......5-30
How to Use This Manual...................................... ii
How to Wear Safety Belts Properly...................1-13
Hydraulic Brake System
Warning Lights............................................3-32
Hydraulic Brake Systems................................... 4-6
Hydraulic Brakes.............................................2-33
Hydroplaning..................................................4-20
7